Install Guide

Figure 56. Path MTU discovery process
IPv6 Neighbor Discovery
The IPv6 neighbor discovery protocol (NDP) is a top-level protocol for neighbor discovery on an IPv6 network.
In place of address resolution protocol (ARP), NDP uses “Neighbor Solicitation” and “Neighbor Advertisement” ICMPv6
messages for determining relationships between neighboring nodes. Using these messages, an IPv6 device learns the link-layer
addresses for neighbors known to reside on attached links, quickly purging cached values that become invalid.
NOTE:
If a neighboring node does not have an IPv6 address assigned, it must be manually pinged to allow the IPv6 device
to determine the relationship of the neighboring node.
NOTE: To avoid problems with network discovery, Dell EMC Networking recommends configuring the static route last or
assigning an IPv6 address to the interface and assigning an address to the peer (the forwarding router’s address) less than
10 seconds apart.
With ARP, each node broadcasts ARP requests on the entire link. This approach causes unnecessary processing by uninterested
nodes. With NDP, each node sends a request only to the intended destination via a multicast address with the unicast address
used as the last 24 bits. Other hosts on the link do not participate in the process, greatly increasing network bandwidth
efficiency.
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IPv6 Routing